1. Field of the Invention
This invention relates to accumulators, and more particularly to such an accumulator for use with pneumatically or hydraulically-actuating devices.
2. Description of the Prior Art
Numerous accumulators of the type described above have been heretofore proposed in the field. A typical prior art accumulator, as shown in FIG. 1, comprises a generally cylindrical main body 1 closed at a bottom end and open at a top end 1a and constituted of a peripheral side wall, and a diaphragm 2 made of flexible material such as rubber and affixed to the inside of the body 1. The diaphragm 2 includes a peripheral side wall interiorly defining a generally cylindrical chamber, and a connector 3 on the circumference of which a spring-acting ring 4 is mounted. Located peripherally of the connector 3 is an outwardly protruded portion 5 arranged for abutting engagement, by means of the action of the ring 4, with a recessed portion 6 formed inwardly peripherally of the body 1 and adjacent to the open end 1a.
Designated at 7 is a cover mounted over the full surface of the open end 1a and secured to the body 1 at their respective joining edges by a lap joint 30 after the diaphragm 2 has been engaged with the body 1. The body 1 is also provided centrally of the cover 7 with an adapter 8 for introducing a gas into the diaphragm chamber, which adapter is closable with a plug 9. To the body is further attached a coupler 10 engageable with a pneumatic or hydraulic device.
However, this conventional accumulator has a drawback in that the formation of the lap joint 30 and also the inward recess requires tedious and time-consuming machining. Another, yet major, drawback is that since the connection of the diaphragm 2 is necessarily positioned adjacent to the lap joint 30 where welding W is effected, the diaphragm 2 per se is prone to deteriorate or degrade due to heat applied during the welding operation which would often in turn result in reduced performance and durability.
Accordingly, from the economic and practical points of view, such a prior art accumulator is totally unsatisfactory in industrial situations.